1. Field of the Invention
The present invention relates to a door for a vehicle, particularly to a side door structure for an automobile which prevents intrusion of the door into a passenger cabin in the case of a side collision.
2. Discussion of the Related Art
A side door for an automobile is provided to a car body part so as to be opened and shut by pivoting on a plurality of vertically spaced hinges. A door lock mechanism and is provided to assist in maintaining the door in a shut/closed condition.
The side door has an inner panel and an outer panel as essential structural components for providing strength to a door. A door lock mechanism and a window regulator are provided in a space between the inner panel and the outer panel. Furthermore, an impact beam of the side door is provided for a passenger""s safety in a lengthwise direction of a vehicle in the space between the inner and outer panels. The impact beam functions as a reinforcement member for preventing the vehicle from intruding or protruding into the passenger cabin of the car when the door is deformed by receiving an impact load from the outer lateral side of the vehicle.
A side door with the impact beam is described in Japanese Kokai Publication 6 (1994)-255365. In the publication, a door structure has hinges and a vertical beam near the hinges, with a bottom end of the vertical beam extending beyond a bottom corner of a door opening. The vertical beam includes a top beam and a bottom beam respectively at upper and lower parts of the vertical beam. The top beam has a front part attached to a top end of the vertical beam and extends as downwardly inclining toward the rear part of the door. On the other hand, the bottom beam has a front part attached to a bottom end of the vertical beam and extends with an upward inclination toward the rear part of the door. Rear ends of the top beam and the bottom beam are fixed to have the rear ends at approximately the same height as that of a bracket surrounding a door lock mechanism.
When an impact load is applied to the top beam and/or the bottom beam from the outer lateral side of the door, the load is dispersed by being transmitted to a door opening frame member via the vertical beam and the bracket. Therefore, the intrusion of a part of the door into the passenger cabin is restricted, and the effect to a passenger sitting near the door is eliminated or minimized.
As shown in FIG. 9, Japanese Kokai Publication 9(1997)-86178 discloses a side door structure wherein a reinforcement member 112 with a U-shaped cross section is provided at a lower part at a door opening 111, and an impact beam 114 in a door main body 113 extends in a lengthwise direction. In the publication, it is proposed to provide the impact beam 114 at a position around the rear portion of the door main body so as to have a center line 114a of the impact beam 114 lower than the reinforcement member 112.
When an impact load is applied to the door main body 113 from the outer lateral side, the rear portion of the impact beam 114 is engaged into a lower part of the reinforcement member 112. In this configuration, it is possible to restrain the intrusion of a lower part of the main body 113, which would be caused by a large deformation of the lower part.
However, an impact load can be applied to the rear part of the door main body, that corresponds to a part relatively near to a passenger seated in the vehicle, from the outer lateral side. This happens relatively often due to the impact of another vehicle from the lateral side. In the side door structure disclosed in Japanese Kokai Publication 6 (1994)-255365, the rear part of the door main body may intrude into a cabin by the deformation of the lower part of the main body.
Moreover, the side door structure in Japanese Kokai Publication 9(1997)-86178 has the drawbacks that the shape of the door opening 111 is complex, and the internal structures contained in the door are revealed when the door is opened so as to mar/degrade the appearance. Furthermore, it is possible that an impact load is applied to the rear part of the door main body 113 at a portion above the rear end of the impact beam 114, namely at a relatively close position to a part where a passenger sits. In this case, the rear portion of the main body 113 can be deformed and intrude into the cabin.
It is therefore a first object of the present invention to provide a side door structure of a vehicle which widely disperses a load applied to a door main body from the outer lateral side thereof to a rear part of the door main body and transmits the load to structural members of the vehicle body so as to prevent the intrusion of the door into a passenger cabin, to minimize an effect on a passenger sitting beside the door, and to restrain a local deformation of the door without marring the appearance of the door when the door is opened, which comprises a door main body with an inner panel provided to face an interior side of the vehicle and an outer panel provided as an exterior side of the vehicle, the inner panel having an inner panel peripheral part, the outer panel having an outer panel peripheral part, the inner panel opposed to the outer panel with the inner panel peripheral part connected with the outer panel peripheral part, the main body superimposed with a door opening frame member of the vehicle so as to have the door main body located on an outer side with respect to a vehicle width; and a rear side reinforcement member provided in the door main body and connecting the inner panel and the outer panel, the rear side reinforcement member, the inner panel and the outer panel defining a rigid part having a closed hollow cross section at a rear part of the door main body.
A second object of the present invention is to provide the side door structure which absorbs the impact energy applied from the outer lateral side of the side door even by the deformation of the rear-side reinforcement member, outer panel and inner panel so as to effectively prevent the intrusion of the door to the passenger cabin further comprising a impact beam provided in the door main body, the impact beam extending in a lengthwise direction of the vehicle and having a rear portion connected to the rear side reinforcement member.
A third object of the present invention is to provide the side door structure wherein the impact load is surely transmitted from the rear part of the door main body to the vehicle body with restricting the movement of the rear part of the door, wherein a front part of the door main body is supported on the door opening frame member by hinges connected therebetween, and a door lock mechanism provided in the door main body adjacent the rear side reinforcement member.
A fourth object of the present invention is to provide a side door structure which disperses a load applied to a door main body from an outer lateral side to a rear part of the door, transmits the load to a vehicle body structural member, absorbs the load even by the deformation of the rear reinforcement member, outer panel and inner panel when a strong impact load is applied so as to prevent the intrusion of the door into a passenger cabin and to minimize an effect on a passenger sitting beside the door without degrading the appearance of the door when the door is opened, comprising a main body formed of an inner panel provided to face at an interior side of the vehicle and an outer panel provided as an exterior side of the vehicle, the inner panel having an inner wall with a peripheral part, and a front face, a bottom face and a rear face formed by bending the inner panel in a direction toward the exterior side of the vehicle, the outer panel having an outer panel peripheral part, the inner panel opposed to the outer panel with the inner panel peripheral part connected with the outer panel peripheral part, the door main body superimposed with a door opening frame member of the vehicle so as to have the main body located on an outer side with respect to a vehicle width; and a rear side reinforcement member provided in the main body so as to face the rear face of the inner panel, the rear side reinforcement member connecting the inner panel and the outer panel, the rear side reinforcement member, the inner panel and the outer panel defining a rigid part with a closed hollow cross section at a rear portion of the door main body.
A fifth object of the present invention is to provide the side door structure which disperses an impact load applied to the main body from the lateral side thereof and widely transmits the impact load to vehicle body structural members even with the deformation of the structural members by preventing the application of a large load directly to a connecting part of the outer panel and the inner panel so as to restrict a rapid deformation of the structural members wherein the rear side reinforcement member comprises a base in the form of a band with an inner edge and an outer edge, the base provided so as to oppose the rear face of the inner panel; an inner flange formed along the inner edge by bending an extended portion from the base and connected to the inner wall of the inner panel; and an outer flange formed along the outer edge by bending an extended portion from the base and connected to the outer panel.
A sixth object of the present invention is to provide the side door structure for the side door with a beautiful external appearance by eliminating the distortion of the outer panel, wherein the outer flange is adhesively connected to the rear face of the outer panel.
A seventh object of the present invention is to provide the side door structure having a strong rear part and capable of effectively dispersing and absorbing impact energy, wherein the rear side reinforcement member comprises a connection part projected from the base and connected with the rear face of the inner panel.
An eighth object of the present invention is to provide the side door structure which effectively absorbs the impact load applied from the lateral side of the door by the deformation of the rear side reinforcement member, outer panel and inner panel by the transmission of the load from the impact beam to structural members of the vehicle body, further comprising a side door impact beam provided in the door, the side door impact beam having an impact beam rear portion and extending in a lengthwise direction of the vehicle, the impact beam rear portion connected to the rear side reinforcement member.
A ninth object of the present invention is to provide the side door structure which effectively transmits an impact load from the rear part of the door main body to structural members of the vehicle body for absorbing the impact energy, wherein the rear face of the inner panel contains an installation wall portion, a face at a lower portion of the outer flange contacted with the installation wall portion.
A tenth object of the present invention is to provide the side door structure capable of effectively preventing the vertical displacement of the rear part of the side-door impact beam by the load application, wherein the impact beam rear portion is connected to the rear side reinforcement member via a bracket which extends to cross in a longitudinal direction of the side door impact beam.
A eleventh object of the present invention is to provide the side door structure wherein the impact load is effectively transmitted from the rear part of the door main body to the structural members of the vehicle with restricting the movement of the rear part of the main body by the side door structure of a vehicle, wherein a front part of the door body is supported on the door opening frame member by the provision of hinges therebetween, and a door lock mechanism is provided in the door main body near the rear side reinforcement member.